body {
    font-family: 'Inter', sans-serif;
    transition: background-color 0.3s, color 0.3s;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
/* Light Theme Variables (OpenAI Inspired) */
:root {
    --bg-color-light: #ffffff;
    --text-color-light: #1C1C1E; /* Slightly off-black for text */
    --card-bg-light: #ffffff;
    --primary-color-light: #007AFF; /* Apple's blue, similar to OpenAI's subtle blue */
    --secondary-color-light: #00A47F; /* A calm teal/green */
    --border-color-light: #E5E5EA; /* Lighter border */
    --header-bg-light: rgba(255, 255, 255, 0.8); /* Semi-transparent for a modern feel */
    --subtle-text-light: #636366;
}
/* Dark Theme Variables (OpenAI Inspired) */
.dark {
    --bg-color-dark: #000000; /* Pure black or very dark gray like #101010 */
    --text-color-dark: #E5E5E5; /* Light gray for text */
    --card-bg-dark: #1C1C1E; /* Slightly lighter than bg for cards */
    --primary-color-dark: #0A84FF; /* Brighter blue for dark mode */
    --secondary-color-dark: #30D158; /* Brighter green for dark mode */
    --border-color-dark: #38383A; /* Darker border */
    --header-bg-dark: rgba(28, 28, 30, 0.8); /* Dark semi-transparent */
    --subtle-text-dark: #8E8E93;
}

/* Applying theme variables */
.theme-light {
    background-color: var(--bg-color-light);
    color: var(--text-color-light);
}
.theme-dark {
    background-color: var(--bg-color-dark);
    color: var(--text-color-dark);
}

.card {
    background-color: var(--card-bg-light);
    border: 1px solid var(--border-color-light);
    box-shadow: 0 1px 3px rgba(0,0,0,0.03), 0 1px 2px rgba(0,0,0,0.03);
}
.dark .card {
    background-color: var(--card-bg-dark);
    border: 1px solid var(--border-color-dark);
    box-shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.1);
}

.header-bg {
    background-color: var(--header-bg-light);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color-light);
}
.dark .header-bg {
    background-color: var(--header-bg-dark);
    border-bottom: 1px solid var(--border-color-dark);
}

.btn-primary {
    background-color: var(--primary-color-light);
    color: white;
    font-weight: 500;
    border-radius: 0.375rem; /* 6px */
}
.dark .btn-primary {
    background-color: var(--primary-color-dark);
    color: var(--bg-color-dark); 
}
.btn-secondary {
    background-color: transparent;
    color: var(--primary-color-light);
    border: 1px solid var(--primary-color-light);
    font-weight: 500;
    border-radius: 0.375rem; /* 6px */
}
.dark .btn-secondary {
    color: var(--primary-color-dark);
    border: 1px solid var(--primary-color-dark);
}
.text-primary {
    color: var(--primary-color-light);
}
.dark .text-primary {
    color: var(--primary-color-dark);
}
.text-secondary {
    color: var(--secondary-color-light);
}
.dark .text-secondary {
    color: var(--secondary-color-dark);
}
.text-subtle {
    color: var(--subtle-text-light);
}
.dark .text-subtle {
    color: var(--subtle-text-dark);
}
.border-theme {
    border-color: var(--border-color-light);
}
.dark .border-theme {
    border-color: var(--border-color-dark);
}

.section-title {
    font-weight: 700;
}

.product-card {
    transition: transform 0.2s ease-out, box-shadow 0.2s ease-out;
}
.product-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.dark .product-card:hover {
     box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}
.nav-link {
    transition: color 0.2s ease-in-out;
    font-weight: 500;
}
.nav-link:hover {
    color: var(--primary-color-light);
}
.dark .nav-link:hover {
    color: var(--primary-color-dark);
}


.btn-fill-effect {
    position: relative;
    overflow: hidden;
    z-index: 1;
    transition: color 0.3s ease;
}

.btn-fill-effect::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0%;
    height: 100%;
    background-color: #0A84FF;
    transition: width 0.3s ease;
    z-index: -1;
}

.btn-fill-effect:hover {
    color: #ffffff;
}

.btn-fill-effect:hover::before {
    width: 100%;
}